import Vue from 'vue';
import { mergeRecursive } from '@/utils/ruoyi';
import DictMeta from './DictMeta';
import DictData from './DictData';

const DEFAULT_DICT_OPTIONS = {
  types: [],
};

/**
 * @classdesc 字典
 * @property {Object} label 标签对象，内部属性名为字典类型名称
 * @property {Object} dict 字段数组，内部属性名为字典类型名称
 * @property {Array.<DictMeta>} _dictMetas 字典元数据数组
 */
export default class Dict {
  constructor() {
    this.owner = null;
    this.label = {};
    this.type = {};
  }

  init(options) {
    if (options instanceof Array) {
      options = { types: options };
    }
    const opts = mergeRecursive(DEFAULT_DICT_OPTIONS, options);
    if (opts.types === undefined) {
      throw new Error('need dict types');
    }
    const ps = [];
    this._dictMetas = opts.types.map((t) => DictMeta.parse(t));
    this._dictMetas.forEach((dictMeta) => {
      const type = dictMeta.type;
      Vue.set(this.label, type, {});
      Vue.set(this.type, type, []);
      if (dictMeta.lazy) {
        return;
      }
      ps.push(loadDict(this, dictMeta));
    });
    return Promise.all(ps);
  }

  /**
   * 重新加载字典
   * @param {String} type 字典类型
   */
  reloadDict(type) {
    const dictMeta = this._dictMetas.find((e) => e.type === type);
    if (dictMeta === undefined) {
      return Promise.reject(`the dict meta of ${type} was not found`);
    }
    return loadDict(this, dictMeta);
  }
}

/**
 * 加载字典
 * @param {Dict} dict 字典
 * @param {DictMeta} dictMeta 字典元数据
 * @returns {Promise}
 */
function loadDict(dict, dictMeta) {
  return dictMeta.request(dictMeta).then((response) => {
    const type = dictMeta.type;
    let dicts = dictMeta.responseConverter(response, dictMeta);
    if (!(dicts instanceof Array)) {
      console.error('the return of responseConverter must be Array.<DictData>');
      dicts = [];
    } else if (
      dicts.filter((d) => d instanceof DictData).length !== dicts.length
    ) {
      console.error('the type of elements in dicts must be DictData');
      dicts = [];
    }
    dict.type[type].splice(0, Number.MAX_SAFE_INTEGER, ...dicts);
    dicts.forEach((d) => {
      Vue.set(dict.label[type], d.value, d.label);
    });
    return dicts;
  });
}
